1. Technical Field
The present invention relates generally to serial interfaces for integrated circuits.
2. Description of the Background Art
Serial interfaces are used to communicate data between devices in a system. Serial interface protocols have been developed at increasingly fast data rates. Examples of industry-standard protocols for serial interfaces include PCI Express® (Peripheral Component Interconnect Express), XAUI (X Attachment Unit Interface), sRIO (serial Rapid IO), and many others.
As the data rates of serial interfaces have increased beyond one gigabit-per-second, jitter has become a significant performance limitation. Jitter relates to the deviation in time of signal transitions from their ideal transition points.
Sources of jitter may be categorized as either random or deterministic. One type of deterministic jitter of particular interest in this case is jitter caused by duty cycle distortion (DCD).